Prior pillow structure, particularly of the "L" shaped pillows and the rectangular pillows are not constructed with an obtuse angle to provide a specific area that is required to give special support to the head of the average side sleeping individual when in the fetal position and when the head is bowed to a forward position along an axis defined by the flexing of the neck. With the usual rectangular pillows of the past, side sleepers having a tendency to rotate their heads forward as they increasingly move into the fetal position so that the side facial area of the head moves off the pillow's bottom edge. This can facilitate an involuntary forward and downward movement of the head, causing the head to roll partly off the pillow and turn downward so that the chin, nose and one cheek rests on the mattress while the back of the head remains elevated by the pillow. This will result in a twist in the neck. Although this position may not be immediately painful or awaken the sleeper, the twist can cause stress on the neck which may produce pain later.
The U.S. Pat. No. 1,386,652 to Patton discloses a pillow having recesses in the longitudinal sides to retain other removable cushions and the provisions to attach the cushions to the main pillow or together to form another pillow. A 10.0 inch radius is the minimum size radius that is large enough to avoid contact with the shoulders while supporting the head. Although a pillow with this radius complies with the teachings of the patent, the radius is unacceptable, being much too small. As the pillow is placed high, at the base of the skull, body movement could cause the pillow to be positioned much lower. The 10.0 radius will then cause the pillow to contact and possibly raise the shoulders. This would be in contradiction to the teachings of the Patton patent. A 20.0 inch radius is the minimum radius suggested for the Patton pillow. This radius is large enough so that when the pillow is at the lower and more proper position behind the head, it does not contact the shoulders. Also, in this lower position, the radius will permit the pillow to have a 0.75 inch clearance with the shoulders. This is allowed to accommodate the larger than average size person without compromising the integrity of the pillow. This radius will also permit the pillow to respond to some body movements without contradicting the teachings of the patent. Therefore, the 20.0 inch radius is the minimum size to meet the criterion of the Patton pillow and not contacting the shoulders when placed behind the head and having the recesses to contain other removable pillow parts. The curvature of the 20.00 inch radius, however, is not nearly sufficient to resemble the contour of the human figure's shoulder. Also, this radius will not allow the Patton pillow to provide the support to the head at the lower jaw.